1. Field of Invention
The present invention relates to the evaluation of print quality of printed documents. More specifically, it relates to the training of a machine to visually inspect print quality. It also relates to the preparation of scanned print samples for evaluation teaching purposes and to image creation of simulated print samples for teaching purposes.
2. Description of Related Art
Assuring the print quality of printers is important in many applications, and particularly important in point-of-sale (POS) commercial applications, which may provide a printed receipt for each commercial transaction. Maintaining the print reliability of such printers is vital to the smooth operation of such commercial establishments.
Often, the only way of determining the print quality of a printer is simply to visually inspect a printout made by the printer. This may be suitable for some applications, such as described in U.S. Pub. 2006/0147092 to Zhang et al., but when qualifying a potential new printer or testing its reliability/quality, it is typically necessary to evaluate a multitude of printouts by the printer being tested. Thus, it is desirable to automate at least some part of the print evaluation process, such as described by Zhang et al.
Another method of automating a print inspection is described in U.S. Pub. 2010/0039510 to Gold et al., which describes using a conveyer belt to image and evaluate specific print types of a known source.
What is needed is a method of not only identifying the text content of a printed document, but also a method of judging the print quality of the print itself. That is, it is not sufficient for an automated system to be able to recognize specific text on a printed document. Rather, it would be preferred that the automated system be cable of judging and scoring the quality of the printout. It is further desirable that the automated system identify areas of the printout that need improving in order to determine what part of a printer should be optimized. For example, it would be desirable for the evaluation to specify whether the print quality suffers due to a low ink supply, due to excessive noise scattering of ink, due to non-uniform darkness over a printed character, etc.
It is an object of the present invention to provide an automated system capable of recognizing, scoring, and categorizing different types of print defects.
It is further an object of the present invention to provide an automated system able to speed up the preprocessing of a printed document in preparation for image inspection.
It is another object of the present invention to provide a system capable of facilitating the gathering of a library of relevant training images for specific types of print errors.